One way I have done this is to remove the suppressor and replace it with
a straight wire. Then take a grid dip meter and couple it tightly to the
wire you just installed and look for the dip. NO POWER TO THE AMP OF
COURSE. The dip will be very narrow and very deep, a sure sign of high
Q. Then install the VHF suppressor, the values of which are not as
critical as some people think, and look for the dip again. Now the dip
should be gone without a trace, not even a tiny wiggle. If you do see a
wiggle, try different combinations of L and R. As a rule, 50 ohms for
the resistor is a good place to start and the L should be the largest
value that will NOT burn up the resistor on the highest frequency the
map will operate at. IOW, if the resistor smokes on ten meters, reduce
the value of L and try again.
And above all, as someone else mentioned, do NOT use carbon composition
resistors. The change value over time and either direction of change
will cause major trouble eventually.
73, Bill W6WRT
On 1/28/2014 2:53 PM, Karel wrote:
I just have to figure out what the factory design should be. I will
definitely use ceramic resistor. Any suggested lead to better
suppressor setup?
Values, arrangement? Thanks,
Karel, VA3KO
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